Use Position and Direction in Particle class

include/openmc/bank.h

@@ -4,23 +4,13 @@
 #include <cstdint>
 #include <vector>
 
-namespace openmc {
-
-struct Bank {
-  double wgt;
-  double xyz[3];
-  double uvw[3];
-  double E;
-  int delayed_group;
-  int particle;
-};
-
-} // namespace openmc
+#include "openmc/particle.h"
+#include "openmc/position.h"
 
 // Without an explicit instantiation of vector<Bank>, the Intel compiler
 // will complain about the threadprivate directive on filter_matches. Note that
 // this has to happen *outside* of the openmc namespace
-extern template class std::vector<openmc::Bank>;
+extern template class std::vector<openmc::Particle::Bank>;
 
 namespace openmc {
 
@@ -32,10 +22,10 @@ namespace simulation {
 
 extern "C" int64_t n_bank;
 
-extern std::vector<Bank> source_bank;
-extern std::vector<Bank> fission_bank;
+extern std::vector<Particle::Bank> source_bank;
+extern std::vector<Particle::Bank> fission_bank;
 #ifdef _OPENMP
-extern std::vector<Bank> master_fission_bank;
+extern std::vector<Particle::Bank> master_fission_bank;
 #endif
 
 #pragma omp threadprivate(fission_bank, n_bank)

include/openmc/capi.h

@@ -6,23 +6,7 @@
 #include <stddef.h>
 
 #ifdef __cplusplus
-#include "openmc/bank.h"
-
 extern "C" {
-  int openmc_fission_bank(openmc::Bank** ptr, int64_t* n);
-  int openmc_source_bank(openmc::Bank** ptr, int64_t* n);
-#else
-  struct Bank {
-    double wgt;
-    double xyz[3];
-    double uvw[3];
-    double E;
-    int delayed_group;
-    int particle;
-  };
-
-  int openmc_fission_bank(struct Bank** ptr, int64_t* n);
-  int openmc_source_bank(struct Bank** ptr, int64_t* n);
 #endif
 
   int openmc_calculate_volumes();
@@ -44,6 +28,7 @@ extern "C" {
   int openmc_filter_set_id(int32_t index, int32_t id);
   int openmc_finalize();
   int openmc_find_cell(const double* xyz, int32_t* index, int32_t* instance);
+  int openmc_fission_bank(void** ptr, int64_t* n);
   int openmc_get_cell_index(int32_t id, int32_t* index);
   int openmc_get_filter_index(int32_t id, int32_t* index);
   void openmc_get_filter_next_id(int32_t* id);
@@ -90,6 +75,7 @@ extern "C" {
   void openmc_set_seed(int64_t new_seed);
   int openmc_simulation_finalize();
   int openmc_simulation_init();
+  int openmc_source_bank(void** ptr, int64_t* n);
   int openmc_spatial_legendre_filter_get_order(int32_t index, int* order);
   int openmc_spatial_legendre_filter_get_params(int32_t index, int* axis, double* min, double* max);
   int openmc_spatial_legendre_filter_set_order(int32_t index, int order);

include/openmc/hdf5_interface.h

@@ -332,7 +332,17 @@ void read_dataset(hid_t obj_id, const char* name, xt::xtensor<T, N>& arr, bool i
 
   // Copy into xtensor
   arr = xarr;
+}
 
+// overload for Position
+inline void
+read_dataset(hid_t obj_id, const char* name, Position& r, bool indep=false)
+{
+  std::array<double, 3> x;
+  read_dataset(obj_id, name, x, indep);
+  r.x = x[0];
+  r.y = x[1];
+  r.z = x[2];
 }
 
 template <typename T, std::size_t N>

include/openmc/math_functions.h

@@ -73,6 +73,8 @@ extern "C" double evaluate_legendre(int n, const double data[], double x);
 
 extern "C" void calc_rn_c(int n, const double uvw[3], double rn[]);
 
+void calc_rn(int n, Direction u, double rn[]);
+
 //==============================================================================
 //! Calculate the n-th order modified Zernike polynomial moment for a given
 //! angle (rho, theta) location on the unit disk.
@@ -131,7 +133,7 @@ extern "C" void calc_zn_rad(int n, double rho, double zn_rad[]);
 
 extern "C" void rotate_angle_c(double uvw[3], double mu, const double* phi);
 
-Direction rotate_angle(Direction u, double mu, double* phi);
+Direction rotate_angle(Direction u, double mu, const double* phi);
 
 //==============================================================================
 //! Samples an energy from the Maxwell fission distribution based on a direct

include/openmc/mesh.h

@@ -101,7 +101,7 @@ public:
   //! \param[in] energies Array of energies
   //! \param[out] Whether any bank sites are outside the mesh
   //! \return Array indicating number of sites in each mesh/energy bin
-  xt::xarray<double> count_sites(int64_t n, const Bank* bank,
+  xt::xarray<double> count_sites(int64_t n, const Particle::Bank* bank,
     int n_energy, const double* energies, bool* outside) const;
 
   int id_ {-1};  //!< User-specified ID

include/openmc/mgxs.h

@@ -158,12 +158,12 @@ class Mgxs {
     //!
     //! @param gin Incoming energy group.
     //! @param sqrtkT Temperature of the material.
-    //! @param uvw Incoming particle direction.
+    //! @param u Incoming particle direction.
     //! @param total_xs Resultant total cross section.
     //! @param abs_xs Resultant absorption cross section.
     //! @param nu_fiss_xs Resultant nu-fission cross section.
     void
-    calculate_xs(int gin, double sqrtkT, const double uvw[3],
+    calculate_xs(int gin, double sqrtkT, Direction u,
          double& total_xs, double& abs_xs, double& nu_fiss_xs);
 
     //! \brief Sets the temperature index in cache given a temperature
@@ -174,9 +174,9 @@ class Mgxs {
 
     //! \brief Sets the angle index in cache given a direction
     //!
-    //! @param uvw Incoming particle direction.
+    //! @param u Incoming particle direction.
     void
-    set_angle_index(const double uvw[3]);
+    set_angle_index(Direction u);
 };
 
 } // namespace openmc

include/openmc/mgxs_interface.h

@@ -48,7 +48,7 @@ void read_mg_cross_sections_header();
 //==============================================================================
 
 extern "C" void
-calculate_xs_c(int i_mat, int gin, double sqrtkT, const double uvw[3],
+calculate_xs_c(int i_mat, int gin, double sqrtkT, Direction u,
      double& total_xs, double& abs_xs, double& nu_fiss_xs);
 
 double

include/openmc/particle.h

@@ -9,7 +9,7 @@
 #include <sstream>
 #include <string>
 
-#include "openmc/capi.h"
+#include "openmc/position.h"
 
 namespace openmc {
 
@@ -33,15 +33,19 @@ constexpr int MAX_LOST_PARTICLES {10};
 // Maximum number of lost particles, relative to the total number of particles
 constexpr double REL_MAX_LOST_PARTICLES {1.0e-6};
 
+//==============================================================================
+// Class declarations
+//==============================================================================
+
 struct LocalCoord {
+  Position r; //!< particle position
+  Direction u; //!< particle direction
   int cell {-1};
   int universe {-1};
   int lattice {-1};
   int lattice_x {-1};
   int lattice_y {-1};
   int lattice_z {-1};
-  double xyz[3]; //!< particle position
-  double uvw[3]; //!< particle direction
   bool rotated {false};  //!< Is the level rotated?
 
   //! clear data from a single coordinate level
@@ -59,6 +63,16 @@ public:
     neutron, photon, electron, positron
   };
 
+  //! Saved ("banked") state of a particle
+  struct Bank {
+    Position r;
+    Direction u;
+    double E;
+    double wgt;
+    int delayed_group;
+    Type particle;
+  };
+
   // Constructors
   Particle();
 
@@ -85,13 +99,13 @@ public:
   bool alive_ {true};     //!< is particle alive?
 
   // Other physical data
-  double last_xyz_current_[3];  //!< coordinates of the last collision or
-                                //!< reflective/periodic surface crossing for
-                                //!< current tallies
-  double last_xyz_[3];          //!< previous coordinates
-  double last_uvw_[3];          //!< previous direction coordinates
-  double last_wgt_ {1.0};       //!< pre-collision particle weight
-  double absorb_wgt_ {0.0};     //!< weight absorbed for survival biasing
+  Position r_last_current_; //!< coordinates of the last collision or
+                            //!< reflective/periodic surface crossing for
+                            //!< current tallies
+  Position r_last_;   //!< previous coordinates
+  Direction u_last_;  //!< previous direction coordinates
+  double last_wgt_ {1.0};   //!< pre-collision particle weight
+  double absorb_wgt_ {0.0}; //!< weight absorbed for survival biasing
 
   // What event took place
   bool fission_ {false}; //!< did particle cause implicit fission
@@ -126,6 +140,18 @@ public:
   int64_t n_secondary_ {};
   Bank secondary_bank_[MAX_SECONDARY];
 
+  Position& r() { return coord_[0].r; }
+  const Position& r() const { return coord_[0].r; }
+
+  Position& r_local() { return coord_[n_coord_ - 1].r; }
+  const Position& r_local() const { return coord_[n_coord_ - 1].r; }
+
+  Direction& u() { return coord_[0].u; }
+  const Direction& u() const { return coord_[0].u; }
+
+  Direction& u_local() { return coord_[n_coord_ - 1].u; }
+  const Direction& u_local() const { return coord_[n_coord_ - 1].u; }
+
   //! resets all coordinate levels for the particle
   void clear();
 
@@ -133,11 +159,10 @@ public:
   //
   //! stores the current phase space attributes of the particle in the
   //! secondary bank and increments the number of sites in the secondary bank.
-  //! \param uvw Direction of the secondary particle
+  //! \param u Direction of the secondary particle
   //! \param E Energy of the secondary particle in [eV]
   //! \param type Particle type
-  //! \param run_CE Whether continuous-energy data is being used
-  void create_secondary(const double* uvw, double E, Type type, bool run_CE);
+  void create_secondary(Direction u, double E, Type type);
 
   //! initialize from a source site
   //

include/openmc/physics.h

@@ -47,7 +47,7 @@ int sample_nuclide(const Particle* p);
 //! Determine the average total, prompt, and delayed neutrons produced from
 //! fission and creates appropriate bank sites.
 void create_fission_sites(Particle* p, int i_nuclide, const Reaction* rx,
-  Bank* bank_array, int64_t* bank_size, int64_t bank_capacity);
+  Particle::Bank* bank_array, int64_t* bank_size, int64_t bank_capacity);
 
 int sample_element(Particle* p);
 
@@ -60,18 +60,18 @@ void absorption(Particle* p, int i_nuclide);
 void scatter(Particle*, int i_nuclide);
 
 //! Treats the elastic scattering of a neutron with a target.
-void elastic_scatter(int i_nuclide, const Reaction* rx, double kT, double* E,
-  double* uvw, double* mu_lab, double* wgt);
+void elastic_scatter(int i_nuclide, const Reaction& rx, double kT, double& E,
+  Direction& u, double& mu_lab);
 
-void sab_scatter(int i_nuclide, int i_sab, double* E,
-  double* uvw, double* mu);
+void sab_scatter(int i_nuclide, int i_sab, double& E,
+  Direction& u, double& mu);
 
 //! samples the target velocity. The constant cross section free gas model is
 //! the default method. Methods for correctly accounting for the energy
 //! dependence of cross sections in treating resonance elastic scattering such
 //! as the DBRC and a new, accelerated scheme are also implemented here.
 Direction sample_target_velocity(const Nuclide* nuc, double E, Direction u,
-   Direction v_neut, double xs_eff, double kT, double* wgt);
+   Direction v_neut, double xs_eff, double kT);
 
 //! samples a target velocity based on the free gas scattering formulation, used
 //! by most Monte Carlo codes, in which cross section is assumed to be constant
@@ -79,7 +79,7 @@ Direction sample_target_velocity(const Nuclide* nuc, double E, Direction u,
 //! FRA-TM-123.
 Direction sample_cxs_target_velocity(double awr, double E, Direction u, double kT);
 
-void sample_fission_neutron(int i_nuclide, const Reaction* rx, double E_in, Bank* site);
+void sample_fission_neutron(int i_nuclide, const Reaction* rx, double E_in, Particle::Bank* site);
 
 //! handles all reactions with a single secondary neutron (other than fission),
 //! i.e. level scattering, (n,np), (n,na), etc.

include/openmc/physics_mg.h

@@ -35,7 +35,7 @@ scatter(Particle* p);
 //! \param size_bank Number of particles currently in the bank
 //! \param bank_array_size Allocated size of the bank
 void
-create_fission_sites(Particle* p, Bank* bank_array, int64_t* size_bank,
+create_fission_sites(Particle* p, Particle::Bank* bank_array, int64_t* size_bank,
      int64_t bank_array_size);
 
 //! \brief Handles an absorption event

include/openmc/position.h

@@ -1,6 +1,7 @@
 #ifndef OPENMC_POSITION_H
 #define OPENMC_POSITION_H
 
+#include <array>
 #include <cmath> // for sqrt
 #include <stdexcept> // for out_of_range
 #include <vector>
@@ -16,7 +17,8 @@ struct Position {
   Position() = default;
   Position(double x_, double y_, double z_) : x{x_}, y{y_}, z{z_} { };
   Position(const double xyz[]) : x{xyz[0]}, y{xyz[1]}, z{xyz[2]} { };
-  Position(const std::vector<double> xyz) : x{xyz[0]}, y{xyz[1]}, z{xyz[2]} { };
+  Position(const std::vector<double>& xyz) : x{xyz[0]}, y{xyz[1]}, z{xyz[2]} { };
+  Position(const std::array<double, 3>& xyz) : x{xyz[0]}, y{xyz[1]}, z{xyz[2]} { };
 
   // Unary operators
   Position& operator+=(Position);
@@ -27,6 +29,7 @@ struct Position {
   Position& operator*=(double);
   Position& operator/=(Position);
   Position& operator/=(double);
+  Position operator-() const;
 
   const double& operator[](int i) const {
     switch (i) {

include/openmc/source.h

@@ -9,7 +9,6 @@
 
 #include "pugixml.hpp"
 
-#include "openmc/bank.h"
 #include "openmc/distribution_multi.h"
 #include "openmc/distribution_spatial.h"
 #include "openmc/particle.h"
@@ -40,7 +39,7 @@ public:
 
   //! Sample from the external source distribution
   //! \return Sampled site
-  Bank sample() const;
+  Particle::Bank sample() const;
 
   // Properties
   double strength() const { return strength_; }
@@ -62,7 +61,7 @@ extern "C" void initialize_source();
 //! Sample a site from all external source distributions in proportion to their
 //! source strength
 //! \return Sampled source site
-Bank sample_external_source();
+Particle::Bank sample_external_source();
 
 //! Fill source bank at end of generation for fixed source simulations
 void fill_source_bank_fixedsource();